================================================================== BUG: KCSAN: data-race in sit_tunnel_xmit / sit_tunnel_xmit read-write to 0xffff88813f22f158 of 8 bytes by task 1856 on cpu 1: sit_tunnel_xmit+0x1be/0x1410 __netdev_start_xmit include/linux/netdevice.h:4840 [inline] netdev_start_xmit include/linux/netdevice.h:4854 [inline] xmit_one+0xc0/0x2a0 net/core/dev.c:3590 dev_hard_start_xmit+0x72/0x120 net/core/dev.c:3606 __dev_queue_xmit+0x91c/0x11c0 net/core/dev.c:4256 dev_queue_xmit include/linux/netdevice.h:3008 [inline] neigh_connected_output+0x25c/0x2d0 net/core/neighbour.c:1600 neigh_output include/net/neighbour.h:546 [inline] ip6_finish_output2+0xa12/0xc30 net/ipv6/ip6_output.c:134 __ip6_finish_output net/ipv6/ip6_output.c:195 [inline] ip6_finish_output+0x395/0x4f0 net/ipv6/ip6_output.c:206 NF_HOOK_COND include/linux/netfilter.h:291 [inline] ip6_output+0x10e/0x210 net/ipv6/ip6_output.c:227 dst_output include/net/dst.h:445 [inline] ip6_local_out+0x60/0x80 net/ipv6/output_core.c:161 ip6tunnel_xmit include/net/ip6_tunnel.h:161 [inline] udp_tunnel6_xmit_skb+0x321/0x4a0 net/ipv6/ip6_udp_tunnel.c:109 send6+0x2ed/0x3b0 drivers/net/wireguard/socket.c:152 wg_socket_send_skb_to_peer+0xbb/0x120 drivers/net/wireguard/socket.c:178 wg_socket_send_buffer_to_peer+0xd2/0xf0 drivers/net/wireguard/socket.c:200 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:40 [inline] wg_packet_handshake_send_worker+0x109/0x150 drivers/net/wireguard/send.c:51 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289 worker_thread+0x618/0xa70 kernel/workqueue.c:2436 kthread+0x1a9/0x1e0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 read-write to 0xffff88813f22f158 of 8 bytes by task 45 on cpu 0: sit_tunnel_xmit+0x1be/0x1410 __netdev_start_xmit include/linux/netdevice.h:4840 [inline] netdev_start_xmit include/linux/netdevice.h:4854 [inline] xmit_one+0xc0/0x2a0 net/core/dev.c:3590 dev_hard_start_xmit+0x72/0x120 net/core/dev.c:3606 __dev_queue_xmit+0x91c/0x11c0 net/core/dev.c:4256 dev_queue_xmit include/linux/netdevice.h:3008 [inline] neigh_connected_output+0x25c/0x2d0 net/core/neighbour.c:1600 neigh_output include/net/neighbour.h:546 [inline] ip6_finish_output2+0xa12/0xc30 net/ipv6/ip6_output.c:134 __ip6_finish_output net/ipv6/ip6_output.c:195 [inline] ip6_finish_output+0x395/0x4f0 net/ipv6/ip6_output.c:206 NF_HOOK_COND include/linux/netfilter.h:291 [inline] ip6_output+0x10e/0x210 net/ipv6/ip6_output.c:227 dst_output include/net/dst.h:445 [inline] ip6_local_out+0x60/0x80 net/ipv6/output_core.c:161 ip6tunnel_xmit include/net/ip6_tunnel.h:161 [inline] udp_tunnel6_xmit_skb+0x321/0x4a0 net/ipv6/ip6_udp_tunnel.c:109 send6+0x2ed/0x3b0 drivers/net/wireguard/socket.c:152 wg_socket_send_skb_to_peer+0xbb/0x120 drivers/net/wireguard/socket.c:178 wg_socket_send_buffer_to_peer+0xd2/0xf0 drivers/net/wireguard/socket.c:200 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:40 [inline] wg_packet_handshake_send_worker+0x109/0x150 drivers/net/wireguard/send.c:51 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289 worker_thread+0x618/0xa70 kernel/workqueue.c:2436 kthread+0x1a9/0x1e0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 value changed: 0x000000000000053b -> 0x000000000000053c Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 45 Comm: kworker/u4:3 Not tainted 6.1.0-rc8-syzkaller-00014-g8ed710da2873-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Workqueue: wg-kex-wg0 wg_packet_handshake_send_worker ==================================================================